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941.
Play-fighting in deer mice, Peromyscus maniculatus bairdii, prairie voles, Microtus ochrogaster, and montane voles, M. Montanus, was compared to that of laboratory rats, Rattus norvegicus. Play in rats appears more complex for two reasons: 1) more of the playful contacts elicit defensive behaviors, and 2) more of these defenses lead to counterattacks, and hence, role reversals between attackers and defenders. Neither high levels of defense, as shown by montane voles, nor high levels of counterattack, as shown by prairie voles, produce rat-like play-fighting. This only occurs when high rates of defense involving turning to face the attacker and counterattack are combined, as in rats. These two components are rarely combined together by deer mice, and so this species rarely exhibits rat-like play-fighting. Furthermore, playful counterattack appears to arise from playful attack, and not from an escalation of defense. These data suggest that the more complex forms of social play, such as play-fighting, have evolved, in part, via the escalation of defense in response to playful attack.  相似文献   
942.
This study evaluated the Children's Firesetting Interview (CFI). The measure was developed to operationalize multiple domains of functioning derived from a riskfactor model of firesetting. The model poses that child, parent, and family characteristics promote firesetting and continuation of a pattern of firesetting. Major factors include curiosity about fire, involvement in and exposure to firerelated activities, and knowledge about first safety The CFI, consisting of 46 questions reflecting six a prioridimensions, was administered to 519 children (ages 6–13) recruited from nonpatient, outpatient, and inpatient samples. Internal consistency and testretest reliability of the measure were satisfactory. Criterion validity was supported by the findings that firesetters showed greater curiosity about fire, involvement in firerelated activities, exposure to models/materials, and knowledge about things that burn than did nonfiresetters. These findings did not vary as a function of the child's patient status or level of antisocial behavior. Implications for the evaluation of firesetting risk are discussed.This study was supported by grant MH-39976 from the Antisocial and Violent Behavior Branch of the National Institute of Mental Health and by a Research Scientist Development Award (MH00353) from the National Institute of Mental Health. The authors acknowledge the constructive suggestions of two anonymous reviewers.  相似文献   
943.
The association of behavior problems with preschool language disorders has been documented extensively. However, researchers have typically failed to differentiate subgroups of language-impaired children, to use observational data in documenting the behavior disorders, or to study children at the youngest ages. Using a multimodal assessment, this study examined parent-child interaction and behavior problems in a clearly defined subgroup of language-impaired children, those with developmental expressive language disorder (ELD). These children exhibit a delay in expressive language compared with receptive language and nonverbal cognitive skills. Subjects were identified and studied at the youngest age at which the disorder can be assessed. A group of ELD children, averaging 27 months of age, was contrasted with a group of normally developing children, matched for age, sex, and receptive language ability. Groups were compared on observed parent-child interactions as well as maternal responses on the Parenting Stress Index, the Eyberg Child Behavior Inventory, and a behavior-related structured interview. ELD children, when compared with normally developing children, exhibited higher levels of negative behavior and were perceived as different by their parents.Portions of these data were presented at the biennial meeting of the Society for Research in Child Development, Baltimore, April 1987, and at the annual meeting of the Society for Pediatrie Research, Anaheim, California, April 1987. This work has been supported by NIMH grant no. 1 R03 MH41603 to author Fischel, and by NICHD grant no. 1 ROI HD19245 to authors Whitehurst and Fischel. It has also been supported by grants of equipment from Commodore Business Machines, Inc., Koala Corporation, and NEC Telephones. We thank the Department of Pediatrics at the Nassau County Medical Center for the use of their facilities.  相似文献   
944.
Subjects were asked to compare the relative depths of two binocular targets embedded in different random dot stereogram backgrounds. The disparities of the background points were either randomized, corresponding to a scattering of points within a volume, or arranged according to a sawtooth (triangle-wave) disparity profile (i.e., a set of slanted planar surfaces separated by sharp depth discontinuities). When the targets were embedded in the random volume, their depths were perceived in accordance with their relative disparities. But when the target points were embedded in the sawtooth surfaces their depths were systematically misperceived in a manner predicted by the incorrect depth interpretation of the background points. Rather than seeing a sawtooth pattern, the background points resembled a staircase in depth, and the targets, which appeared embedded in different steps, were misjudged in depth accordingly. The effect suggests a distinction between the depth processing of isolated binocular features and those associated with continuous surfaces.  相似文献   
945.
Subjects saw kinetic depth displays whose shape (sphere or cylinder) was defined by luminous dots distributed randomly on the surface or in the volume of the object. Subjects rated perceived 3-D depth, rigidity, and coherence. Despite individual differences, all 3 ratings increased with the number of dots. Dots in the volume yielded ratings equal to or greater than surface dots. Each rating varied with 3 of 4 factors (shape, distribution, numerosity, and perspective), but the ratings either between trials or between conditions were often uncorrelated. Object shape affected rigidity but not depth ratings. Veridically perceived polar displays had slightly lower rigidity but higher depth ratings than parallel projection displays. (Reversed polar displays were always grossly nonrigid.) The interaction of ratings and stimulus parameters requires theories and experiments in which different KDE ratings are not treated interchangeably.  相似文献   
946.
Generativity is the concern for guiding and promoting the next generation through such creative behavior as parenting, teaching, mentoring, leading, and generating products and outcomes that benefit others. Erikson (1963) has argued that in order to be generative in adulthood, people must have a fundamental “belief in the species” or a faith that human progress is possible and worth working toward. The present study focuses on hope and trust concerning the self and others (Erikson's “belief in the species”). In addition, however, the study examines the relation between generativity and personality traits, in this case, dominance, leadership, self-absorption, and nurturance. A sample of 70 adults was administered (1) a series of self-report questionnaires converging on Erikson's idea of belief in the species, (2) a self-report scale assessing generativity, (3) measures of personality traits, and (4) two open-ended measures of generativity requiring subjects to describe life commitments and creative endeavors. The results provide modest support for Erikson's claim of a link between belief in the species and generativity, with significant positive correlations obtained (1) between self-report generativity and two measures of belief in species and (2) between generativity assessed through life commitments and one measure of belief in the species. In addition, the personality trait of nurturance was positively related to all three generativity measures. Problems and issues in the assessment of generativity are discussed.  相似文献   
947.
Two groups of singers (n = 12,13) and a group of nonsingers (n = 12) each produced the national anthem by (1) speaking and (2) singing the words and by (3) humming the melody. Regional cerebral blood flow (rCBF) was measured at rest and during each phonation task from seven areas in each hemisphere by the 133Xe-inhalation method. Intrahemisphere, interhemisphere, and global rCBF were generally similar across phonation tasks and did not yield appreciable differences among the nonsingers and the singers.  相似文献   
948.
Three hemifield tachistoscopic studies of a right-handed patient with acquired Broca's aphasia and deep dyslexia, but with intact visual fields, are presented to support the hypothesis of right hemisphere (RH) participation in deep dyslexic reading. A systematic comparison of this deep dyslexic with the disconnected RHs of two patients with complete cerebral commissurotomy disclosed a similar, but not identical, pattern of abilities. The results demonstrate partial reliance on the RH for accessing the meaning of single words, but not for phonological encoding in this patient.  相似文献   
949.
The possibility was explored that the informativeness of a specific region within a word can influence eye movements during reading. In Experiment 1, words containing identifying information either toward the beginning or toward the end were displayed asymmetrically around the point of fixation so that the reader was initially presented with either the informative or noninformative zone. Words were read with shorter summed initial fixation time when the reading was started from the informative zone. In Experiments 2 and 3, the target words were presented in sentences that were to be comprehended. More attention was given to the informative endings of words than to redundant endings. The latter were also skipped more often. The duration of the first fixation was not affected by information distribution within the word, whereas the second fixation duration was. The results of these experiments lend good support to the hypothesis of immediate lexical control over fixation behavior and to the notion of a convenient viewing position.  相似文献   
950.
A total of 178 reading disabled children were randomly assigned to one of three treatment conditions providing training in word recognition and decoding skills (DS), oral and written language (OWLS), or classroom survival skills (CSS. an alternative treatment control). Pre- and post-treatment comparisons on an array of standardized and experimental measures indicated that the two experimental treatments (DS, OWLS) resulted in improvement on selected tests significantly greater than that resulting from a third treatment intervention which controlled for treatment time and individual attention (CSS). Effects specific to each experimental treatment were identified, as well as some generalized treatment advantages shared by both experimental groups at post-test. These results indicate that some of the deficits associated with developmental dyslexia are amenable to treatment. Greater generalization of treatment effects was observed following the DS than the OWLS treatment. While DS-instructed children exhibited better word recognition skills, however, their knowledge of grapheme-phoneme correspondence rules was not improved. Several OWLS-specific effects observed on experimental reading and language measures were not replicated on standardized tests which purport to measure the same skills. These results are discussed with respect to (i) possible mechanisms by which disabled readers may acquire word recognition skills, (ii) their failure to acquire and use grapheme-phoneme correspondence rules, and (iii) a possible reduced tendency in the present population to generalize newly acquired specific knowledge to related knowledge domains.  相似文献   
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